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4AGZE Turbo – Part 1


4AGZE Turbo – Part 1


Part 1 – Sourcing the hardware.

For the past few months I’ve been collecting the necessary parts to perform the 4A-GTE conversion into my AE92 Seca. The plan was originally to turbocharge the 20v currently in my car, which, going by other’s results (i.e. Sam’s 12second turbo 20v Corolla), has the potential to make serious HP. After considering the hassle involved in running forced induction on an engine that was never designed for it (for example- quad throttles, high compression) I decided that using a 4A-GZE as the base would be a more cost effective and reliable option. This was a tough decision because I love the 20v, but the advantages of coated pistons, oil squirters, a strengthened bottom-end and a compression ratio (8.8:1) more suited to forced induction made the MAP-sensored 4A-GZE the obvious choice. Who knows, maybe one day the 20v head will find it’s way onto the GZE block…

Anyway, on to the goodies I’m using to turbocharge the 4A-GZE (price summary at bottom of page):
The first part to find it’s way into my shed was a custom exhaust manifold made from steam pipe – it apparently originated from Sam’s Turbo 4A-GZE before it had the 20v head. With the manifold also came a T28 turbo (from a 12A rotary) which mates straight up to the exhaust flange.

At this stage I came to the decision to use a GZE instead of the 20v, so I purchased a Microtech Digi 1+ from Jamie, the same guy who sold me the turbo & manifold (I was originally going to buy a new Link or Microtech MT-8). The Microtech has a loom to suit the 4A-GZE but unfortunately is only suited to single coil operation and not the GZE dual coil-pack setup, requiring the use of a distributor and coil from a normal 4A-GE (not a major problem).

I also picked up a coil-pack (above, beside dizzy) and radiator (below) from a 100kw when I bought the inlet manifold, which should make things easier when it’s time to do the swap. Thanks Phil!

I purchased the GZE intercooler (above, didn’t come with the long-motor) from AllJap, I figure that for $125 it is worth using at least to begin with, as it’s supposed to have fairly decent cooling & flow properties. Of course if big boost is to be run at some stage in the future, this will have to be upgraded to a larger core.

With most of the major parts sorted out, I figured it would probably help if I had an engine to use them on. AllJap Auto Parts (Sandgate Rd, Virginia) supplied a MAP-sensored 4A-GZE minus the supercharger, gearbox, mounts, air-con, power-steering, half the hoses and (literally) half the wiring loom. This was definitely a cheap way to buy the engine, but after seeing the way everything has been just chopped out of the car, I think I would consider spending the extra on a half-cut next time. Thankfully I don’t need most of the wiring loom as I’m running an aftermarket computer, but the amount of hoses that are going to need replacing is certainly going to add up to a few dollars. I should also mention that I had a few hassles with AllJap, in that they actually sold the engine I had put a deposit on to somebody else, but to their credit they brought another one up from their store down the Gold Coast the same day and stayed back late on a Friday pulling the gearbox/supercharger/etc off so I could pick it up that evening.

Current pricing breakdown:  
Exhaust Manifold & T28 Turbo $600
Microtech Digi 1+ computer & Distributor $650
Inlet Manifold $100
Coil Assembly $30
Radiator $60
AE101 MAP-sensored 4A-GZE $695
4A-GZE Intercooler $125
Subtotal $2250
The second part to this build-up process will become available as the engine is prepared for installation into the Corolla in it’s turbo-form. The third and final part will detail the installation and the results.
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